Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!srhqla!demott!kdq
From: kdq@demott.COM (Kevin D. Quitt)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: **** WANTED **** BINARY FILE COPY PROGRAM
Message-ID: <598@demott.COM>
Date: 21 Sep 90 15:45:49 GMT
References: <6177@uceng.UC.EDU>
Reply-To: kdq@demott.COM (Kevin D. Quitt)
Organization: DeMott Electronics Co., Van Nuys CA
Lines: 23

In article <6177@uceng.UC.EDU> dsims@uceng.UC.EDU (david l sims) writes:
>
>For those who aren't sure how to buffer their program, one solution is
>to perform read's and write's in, say, 10000 byte blocks, instead of the
>usual and simple method of reading and writing one character at a time.


    To perform the fastest file copies, make sure you have buffer space to
read an entire track at once.  More than that won't speed you up.  The
best way is to actually figure the hardware sector number of the file
and read tracks as much as possible.  This, of course, doesn't work if the
file isn't contiguous.

    The BIOS won't read past the end of a track in a single request - it'll
break it up into pieces, and you'll lose revs.  Reading tracks on a floppy
can give you 4 times the speed.
-- 
 _
Kevin D. Quitt         demott!kdq   kdq@demott.com
DeMott Electronics Co. 14707 Keswick St.   Van Nuys, CA 91405-1266
VOICE (818) 988-4975   FAX (818) 997-1190  MODEM (818) 997-4496 PEP last

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